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/* Copyright (C) 2017 The Android Open Source Project
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This file implements interfaces from the file jvmti.h. This implementation
* is licensed under the same terms as the file jvmti.h. The
* copyright and license information for the file jvmti.h follows.
*
* Copyright (c) 2003, 2011, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
#include <vector>
#include "jvmti.h"
#include "ti_extension.h"
#include "art_jvmti.h"
#include "events.h"
#include "jni_id_type.h"
#include "runtime-inl.h"
#include "ti_allocator.h"
#include "ti_class.h"
#include "ti_ddms.h"
#include "ti_dump.h"
#include "ti_heap.h"
#include "ti_logging.h"
#include "ti_monitor.h"
#include "ti_redefine.h"
#include "ti_search.h"
#include "transform.h"
#include "thread-inl.h"
namespace openjdkjvmti {
struct CParamInfo {
const char* name;
jvmtiParamKind kind;
jvmtiParamTypes base_type;
jboolean null_ok;
jvmtiParamInfo ToParamInfo(jvmtiEnv* env,
/*out*/std::vector<JvmtiUniquePtr<char[]>>* char_buffers,
/*out*/jvmtiError* err) const {
JvmtiUniquePtr<char[]> param_name = CopyString(env, name, err);
char* name_ptr = param_name.get();
char_buffers->push_back(std::move(param_name));
return jvmtiParamInfo{ name_ptr, kind, base_type, null_ok };
}
};
jvmtiError ExtensionUtil::GetExtensionFunctions(jvmtiEnv* env,
jint* extension_count_ptr,
jvmtiExtensionFunctionInfo** extensions) {
if (extension_count_ptr == nullptr || extensions == nullptr) {
return ERR(NULL_POINTER);
}
std::vector<jvmtiExtensionFunctionInfo> ext_vector;
// Holders for allocated values.
std::vector<JvmtiUniquePtr<char[]>> char_buffers;
std::vector<JvmtiUniquePtr<jvmtiParamInfo[]>> param_buffers;
std::vector<JvmtiUniquePtr<jvmtiError[]>> error_buffers;
auto add_extension = [&](jvmtiExtensionFunction func,
const char* id,
const char* short_description,
const std::vector<CParamInfo>& params,
const std::vector<jvmtiError>& errors) {
jvmtiExtensionFunctionInfo func_info;
jvmtiError error;
func_info.func = func;
JvmtiUniquePtr<char[]> id_ptr = CopyString(env, id, &error);
if (id_ptr == nullptr) {
return error;
}
func_info.id = id_ptr.get();
char_buffers.push_back(std::move(id_ptr));
JvmtiUniquePtr<char[]> descr = CopyString(env, short_description, &error);
if (descr == nullptr) {
return error;
}
func_info.short_description = descr.get();
char_buffers.push_back(std::move(descr));
func_info.param_count = params.size();
if (!params.empty()) {
JvmtiUniquePtr<jvmtiParamInfo[]> params_ptr =
AllocJvmtiUniquePtr<jvmtiParamInfo[]>(env, params.size(), &error);
if (params_ptr == nullptr) {
return error;
}
func_info.params = params_ptr.get();
param_buffers.push_back(std::move(params_ptr));
for (jint i = 0; i != func_info.param_count; ++i) {
func_info.params[i] = params[i].ToParamInfo(env, &char_buffers, &error);
if (error != OK) {
return error;
}
}
} else {
func_info.params = nullptr;
}
func_info.error_count = errors.size();
if (!errors.empty()) {
JvmtiUniquePtr<jvmtiError[]> errors_ptr =
AllocJvmtiUniquePtr<jvmtiError[]>(env, errors.size(), &error);
if (errors_ptr == nullptr) {
return error;
}
func_info.errors = errors_ptr.get();
error_buffers.push_back(std::move(errors_ptr));
for (jint i = 0; i != func_info.error_count; ++i) {
func_info.errors[i] = errors[i];
}
} else {
func_info.errors = nullptr;
}
ext_vector.push_back(func_info);
return ERR(NONE);
};
jvmtiError error;
// Heap extensions.
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(HeapExtensions::GetObjectHeapId),
"com.android.art.heap.get_object_heap_id",
"Retrieve the heap id of the the object tagged with the given argument. An "
"arbitrary object is chosen if multiple objects exist with the same tag.",
{
{ "tag", JVMTI_KIND_IN, JVMTI_TYPE_JLONG, false},
{ "heap_id", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false}
},
{ JVMTI_ERROR_NOT_FOUND });
if (error != ERR(NONE)) {
return error;
}
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(HeapExtensions::GetHeapName),
"com.android.art.heap.get_heap_name",
"Retrieve the name of the heap with the given id.",
{
{ "heap_id", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false},
{ "heap_name", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_CCHAR, false}
},
{ JVMTI_ERROR_ILLEGAL_ARGUMENT });
if (error != ERR(NONE)) {
return error;
}
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(HeapExtensions::IterateThroughHeapExt),
"com.android.art.heap.iterate_through_heap_ext",
"Iterate through a heap. This is equivalent to the standard IterateThroughHeap function,"
" except for additionally passing the heap id of the current object. The jvmtiHeapCallbacks"
" structure is reused, with the callbacks field overloaded to a signature of "
"jint (*)(jlong, jlong, jlong*, jint length, void*, jint).",
{
{ "heap_filter", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false},
{ "klass", JVMTI_KIND_IN, JVMTI_TYPE_JCLASS, true},
{ "callbacks", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CVOID, false},
{ "user_data", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CVOID, true}
},
{
ERR(MUST_POSSESS_CAPABILITY),
ERR(INVALID_CLASS),
ERR(NULL_POINTER),
});
if (error != ERR(NONE)) {
return error;
}
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(AllocUtil::GetGlobalJvmtiAllocationState),
"com.android.art.alloc.get_global_jvmti_allocation_state",
"Returns the total amount of memory currently allocated by all jvmtiEnvs through the"
" 'Allocate' jvmti function. This does not include any memory that has been deallocated"
" through the 'Deallocate' function. This number is approximate and might not correspond"
" exactly to the sum of the sizes of all not freed allocations.",
{
{ "currently_allocated", JVMTI_KIND_OUT, JVMTI_TYPE_JLONG, false},
},
{ ERR(NULL_POINTER) });
if (error != ERR(NONE)) {
return error;
}
// DDMS extension
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(DDMSUtil::HandleChunk),
"com.android.art.internal.ddm.process_chunk",
"Handles a single ddms chunk request and returns a response. The reply data is in the ddms"
" chunk format. It returns the processed chunk. This is provided for backwards compatibility"
" reasons only. Agents should avoid making use of this extension when possible and instead"
" use the other JVMTI entrypoints explicitly.",
{
{ "type_in", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "length_in", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "data_in", JVMTI_KIND_IN_BUF, JVMTI_TYPE_JBYTE, true },
{ "type_out", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false },
{ "data_len_out", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false },
{ "data_out", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_JBYTE, false }
},
{ ERR(NULL_POINTER), ERR(ILLEGAL_ARGUMENT), ERR(OUT_OF_MEMORY) });
if (error != ERR(NONE)) {
return error;
}
// GetClassLoaderClassDescriptors extension
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(ClassUtil::GetClassLoaderClassDescriptors),
"com.android.art.class.get_class_loader_class_descriptors",
"Retrieves a list of all the classes (as class descriptors) that the given class loader is"
" capable of being the defining class loader for. The return format is a list of"
" null-terminated descriptor strings of the form \"L/java/lang/Object;\". Each descriptor"
" will be in the list at most once. If the class_loader is null the bootclassloader will be"
" used. If the class_loader is not null it must either be a java.lang.BootClassLoader, a"
" dalvik.system.BaseDexClassLoader or a derived type. The data_out list and all elements"
" must be deallocated by the caller.",
{
{ "class_loader", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, true },
{ "class_descriptor_count_out", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false },
{ "data_out", JVMTI_KIND_ALLOC_ALLOC_BUF, JVMTI_TYPE_CCHAR, false },
},
{
ERR(NULL_POINTER),
ERR(ILLEGAL_ARGUMENT),
ERR(OUT_OF_MEMORY),
ERR(NOT_IMPLEMENTED),
});
if (error != ERR(NONE)) {
return error;
}
// Raw monitors no suspend
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(MonitorUtil::RawMonitorEnterNoSuspend),
"com.android.art.concurrent.raw_monitor_enter_no_suspend",
"Normally entering a monitor will not return until both the monitor is locked and the"
" current thread is not suspended. This method will return once the monitor is locked"
" even if the thread is suspended. Note that using rawMonitorWait will wait until the"
" thread is not suspended again on wakeup and so should be avoided.",
{
{ "raw_monitor", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CVOID, false },
},
{
ERR(NULL_POINTER),
ERR(INVALID_MONITOR),
});
if (error != ERR(NONE)) {
return error;
}
// GetLastError extension
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(LogUtil::GetLastError),
"com.android.art.misc.get_last_error_message",
"In some cases the jvmti plugin will log data about errors to the android logcat. These can"
" be useful to tools so we make (some) of the messages available here as well. This will"
" fill the given 'msg' buffer with the last non-fatal message associated with this"
" jvmti-env. Note this is best-effort only, not all log messages will be accessible through"
" this API. This will return the last error-message from all threads. Care should be taken"
" interpreting the return value when used with a multi-threaded program. The error message"
" will only be cleared by a call to 'com.android.art.misc.clear_last_error_message' and will"
" not be cleared by intervening successful calls. If no (tracked) error message has been"
" sent since the last call to clear_last_error_message this API will return"
" JVMTI_ERROR_ABSENT_INFORMATION. Not all failures will cause an error message to be"
" recorded.",
{
{ "msg", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_CCHAR, false },
},
{
ERR(NULL_POINTER),
ERR(ABSENT_INFORMATION),
});
if (error != ERR(NONE)) {
return error;
}
// ClearLastError extension
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(LogUtil::ClearLastError),
"com.android.art.misc.clear_last_error_message",
"Clears the error message returned by 'com.android.art.misc.get_last_error_message'.",
{ },
{ });
if (error != ERR(NONE)) {
return error;
}
// DumpInternalState
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(DumpUtil::DumpInternalState),
"com.android.art.misc.get_plugin_internal_state",
"Gets internal state about the plugin and serializes it to the given msg. "
"There is no particular format to this message beyond being human readable.",
{
{ "msg", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_CCHAR, false },
},
{ ERR(NULL_POINTER) });
if (error != ERR(NONE)) {
return error;
}
// AddToDexClassLoader
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(SearchUtil::AddToDexClassLoader),
"com.android.art.classloader.add_to_dex_class_loader",
"Adds a dexfile to a given dalvik.system.BaseDexClassLoader in a manner similar to"
" AddToSystemClassLoader.",
{
{ "classloader", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, false },
{ "segment", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CCHAR, false },
},
{
ERR(NULL_POINTER),
ERR(CLASS_LOADER_UNSUPPORTED),
ERR(ILLEGAL_ARGUMENT),
ERR(WRONG_PHASE),
});
if (error != ERR(NONE)) {
return error;
}
// AddToDexClassLoaderInMemory
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(SearchUtil::AddToDexClassLoaderInMemory),
"com.android.art.classloader.add_to_dex_class_loader_in_memory",
"Adds a dexfile buffer to a given dalvik.system.BaseDexClassLoader in a manner similar to"
" AddToSystemClassLoader. This may only be done during the LIVE phase. The buffer is copied"
" and the caller is responsible for deallocating it after this call.",
{
{ "classloader", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, false },
{ "dex_bytes", JVMTI_KIND_IN_BUF, JVMTI_TYPE_CCHAR, false },
{ "dex_bytes_len", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
},
{
ERR(NULL_POINTER),
ERR(CLASS_LOADER_UNSUPPORTED),
ERR(ILLEGAL_ARGUMENT),
ERR(WRONG_PHASE),
});
if (error != ERR(NONE)) {
return error;
}
// ChangeArraySize
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(HeapExtensions::ChangeArraySize),
"com.android.art.heap.change_array_size",
"Changes the size of a java array. As far as all JNI and java code is concerned this is"
" atomic. Must have can_tag_objects capability. If the new length of the array is smaller"
" than the original length, then the array will be truncated to the new length. Otherwise,"
" all new slots will be filled with null, 0, or False as appropriate for the array type.",
{
{ "array", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, false },
{ "new_size", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
},
{
ERR(NULL_POINTER),
ERR(MUST_POSSESS_CAPABILITY),
ERR(ILLEGAL_ARGUMENT),
ERR(OUT_OF_MEMORY),
});
if (error != ERR(NONE)) {
return error;
}
// These require index-ids and debuggable to function
art::Runtime* runtime = art::Runtime::Current();
if (runtime->GetJniIdType() == art::JniIdType::kIndices && IsFullJvmtiAvailable()) {
// IsStructurallyModifiableClass
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(Redefiner::IsStructurallyModifiableClass),
"com.android.art.class.is_structurally_modifiable_class",
"Returns whether a class can potentially be 'structurally' redefined using the various"
" structural redefinition extensions provided.",
{
{ "klass", JVMTI_KIND_IN, JVMTI_TYPE_JCLASS, false },
{ "result", JVMTI_KIND_OUT, JVMTI_TYPE_JBOOLEAN, false },
},
{
ERR(INVALID_CLASS),
ERR(NULL_POINTER),
});
if (error != ERR(NONE)) {
return error;
}
// StructurallyRedefineClasses
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(Redefiner::StructurallyRedefineClasses),
"com.android.art.class.structurally_redefine_classes",
"Entrypoint for structural class redefinition. Has the same signature as RedefineClasses."
" Only supports additive changes, methods and fields may not be removed. Supertypes and"
" implemented interfaces may not be changed. After calling this"
" com.android.art.structural_dex_file_load_hook events will be triggered, followed by"
" re-transformable ClassFileLoadHook events. After this method completes subsequent"
" RetransformClasses calls will use the input to this function as the initial class"
" definition.",
{
{ "num_classes", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "class_definitions", JVMTI_KIND_IN_BUF, JVMTI_TYPE_CVOID, false },
},
{
ERR(CLASS_LOADER_UNSUPPORTED),
ERR(FAILS_VERIFICATION),
ERR(ILLEGAL_ARGUMENT),
ERR(INVALID_CLASS),
ERR(MUST_POSSESS_CAPABILITY),
ERR(MUST_POSSESS_CAPABILITY),
ERR(NULL_POINTER),
ERR(OUT_OF_MEMORY),
ERR(UNMODIFIABLE_CLASS),
ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED),
ERR(UNSUPPORTED_REDEFINITION_METHOD_ADDED),
ERR(UNSUPPORTED_REDEFINITION_METHOD_DELETED),
ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED),
});
if (error != ERR(NONE)) {
return error;
}
// StructurallyRedefineClassDirect
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(Redefiner::StructurallyRedefineClassDirect),
"com.android.art.UNSAFE.class.structurally_redefine_class_direct",
"Temporary prototype entrypoint for redefining a single class structurally. Currently this"
" only supports adding new static fields to a class without any instances."
" ClassFileLoadHook events will NOT be triggered. This does not currently support creating"
" obsolete methods. This function only has rudimentary error checking. This should not be"
" used except for testing.",
{
{ "klass", JVMTI_KIND_IN, JVMTI_TYPE_JCLASS, false },
{ "new_def", JVMTI_KIND_IN_BUF, JVMTI_TYPE_CCHAR, false },
{ "new_def_len", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
},
{
ERR(CLASS_LOADER_UNSUPPORTED),
ERR(FAILS_VERIFICATION),
ERR(ILLEGAL_ARGUMENT),
ERR(INVALID_CLASS),
ERR(MUST_POSSESS_CAPABILITY),
ERR(MUST_POSSESS_CAPABILITY),
ERR(NULL_POINTER),
ERR(OUT_OF_MEMORY),
ERR(UNMODIFIABLE_CLASS),
ERR(UNSUPPORTED_REDEFINITION_HIERARCHY_CHANGED),
ERR(UNSUPPORTED_REDEFINITION_METHOD_ADDED),
ERR(UNSUPPORTED_REDEFINITION_METHOD_DELETED),
ERR(UNSUPPORTED_REDEFINITION_SCHEMA_CHANGED),
});
if (error != ERR(NONE)) {
return error;
}
} else {
LOG(INFO) << "debuggable & jni-type indices are required to implement structural "
<< "class redefinition extensions.";
}
// SetVerboseFlagExt
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(LogUtil::SetVerboseFlagExt),
"com.android.art.misc.set_verbose_flag_ext",
"Sets the verbose flags selected by the 'option' c-string. Valid options are anything that"
" would be accepted by the -verbose:<option> runtime flag. The verbose selections are turned"
" on if 'enable' is set to true and disabled otherwise. You may select multiple options at"
" once using commas just like with the -verbose:<option> flag. For example \"class,deopt,gc\""
" is equivalent to turning on all of the VLOG(class_linker), VLOG(deopt) and VLOG(gc)"
" messages.",
{
{ "option", JVMTI_KIND_IN_BUF, JVMTI_TYPE_CCHAR, false },
{ "enable", JVMTI_KIND_IN, JVMTI_TYPE_JBOOLEAN, false },
},
{
ERR(NULL_POINTER),
ERR(ILLEGAL_ARGUMENT),
});
if (error != ERR(NONE)) {
return error;
}
// GetHiddenApiEnforcementPolicy
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(ClassUtil::GetHiddenApiEnforcementPolicy),
"com.android.art.misc.get_hidden_api_enforcement_policy",
"Gets the current hiddenapi enforcement policy. Policy values are defined in"
" `frameworks/base/core/java/android/content/pm/ApplicationInfo.java` as the"
" HIDDEN_API_ENFORCEMENT_ static fields. See the comments in `art/runtime/hidden_api.h` for"
" more information. This should be used with"
" `com.android.art.misc.set_hidden_api_enforcement_policy` in order to restore the"
" hidden-api state after temporarily toggling it.",
{
{ "policy", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false },
},
{
ERR(NULL_POINTER),
});
if (error != ERR(NONE)) {
return error;
}
// SetHiddenApiEnforcementPolicy
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(ClassUtil::SetHiddenApiEnforcementPolicy),
"com.android.art.misc.set_hidden_api_enforcement_policy",
"Sets the hiddenapi enforcement policy to the given value. Policy values are defined in"
" `frameworks/base/core/java/android/content/pm/ApplicationInfo.java` as the"
" HIDDEN_API_ENFORCEMENT_ static fields. See the comments in `art/runtime/hidden_api.h` for"
" more information. This API should always be used sparingly and in conjunction with"
" `com.android.art.misc.get_hidden_api_enforcement_policy` to temporarily toggle"
" hidden-api on and off as changes are required.",
{
{ "policy", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
},
{
ERR(ILLEGAL_ARGUMENT),
});
if (error != ERR(NONE)) {
return error;
}
// DisableHiddenApiEnforcementPolicy
error = add_extension(
reinterpret_cast<jvmtiExtensionFunction>(ClassUtil::DisableHiddenApiEnforcementPolicy),
"com.android.art.misc.disable_hidden_api_enforcement_policy",
"Sets the hiddenapi enforcement policy to disabled. This API should always be"
" used sparingly and in conjunction with"
" `com.android.art.misc.get_hidden_api_enforcement_policy` and"
" `com.android.art.misc.set_hidden_api_enforcement_policy` to temporarily"
" toggle hidden-api on and off as changes are required.",
{},
{});
if (error != ERR(NONE)) {
return error;
}
// Copy into output buffer.
*extension_count_ptr = ext_vector.size();
JvmtiUniquePtr<jvmtiExtensionFunctionInfo[]> out_data =
AllocJvmtiUniquePtr<jvmtiExtensionFunctionInfo[]>(env, ext_vector.size(), &error);
if (out_data == nullptr) {
return error;
}
memcpy(out_data.get(),
ext_vector.data(),
ext_vector.size() * sizeof(jvmtiExtensionFunctionInfo));
*extensions = out_data.release();
// Release all the buffer holders, we're OK now.
for (auto& holder : char_buffers) {
holder.release();
}
for (auto& holder : param_buffers) {
holder.release();
}
for (auto& holder : error_buffers) {
holder.release();
}
return OK;
}
jvmtiError ExtensionUtil::GetExtensionEvents(jvmtiEnv* env,
jint* extension_count_ptr,
jvmtiExtensionEventInfo** extensions) {
std::vector<jvmtiExtensionEventInfo> ext_vector;
// Holders for allocated values.
std::vector<JvmtiUniquePtr<char[]>> char_buffers;
std::vector<JvmtiUniquePtr<jvmtiParamInfo[]>> param_buffers;
auto add_extension = [&](ArtJvmtiEvent extension_event_index,
const char* id,
const char* short_description,
const std::vector<CParamInfo>& params) {
DCHECK(IsExtensionEvent(extension_event_index)) << static_cast<jint>(extension_event_index);
jvmtiExtensionEventInfo event_info;
jvmtiError error;
event_info.extension_event_index = static_cast<jint>(extension_event_index);
JvmtiUniquePtr<char[]> id_ptr = CopyString(env, id, &error);
if (id_ptr == nullptr) {
return error;
}
event_info.id = id_ptr.get();
char_buffers.push_back(std::move(id_ptr));
JvmtiUniquePtr<char[]> descr = CopyString(env, short_description, &error);
if (descr == nullptr) {
return error;
}
event_info.short_description = descr.get();
char_buffers.push_back(std::move(descr));
event_info.param_count = params.size();
if (!params.empty()) {
JvmtiUniquePtr<jvmtiParamInfo[]> params_ptr =
AllocJvmtiUniquePtr<jvmtiParamInfo[]>(env, params.size(), &error);
if (params_ptr == nullptr) {
return error;
}
event_info.params = params_ptr.get();
param_buffers.push_back(std::move(params_ptr));
for (jint i = 0; i != event_info.param_count; ++i) {
event_info.params[i] = params[i].ToParamInfo(env, &char_buffers, &error);
if (error != OK) {
return error;
}
}
} else {
event_info.params = nullptr;
}
ext_vector.push_back(event_info);
return ERR(NONE);
};
jvmtiError error;
error = add_extension(
ArtJvmtiEvent::kDdmPublishChunk,
"com.android.art.internal.ddm.publish_chunk_safe",
"Called when there is new ddms information that the agent or other clients can use. The"
" agent is given the 'type' of the ddms chunk and a 'data_size' byte-buffer in 'data'."
" The 'data' pointer is only valid for the duration of the publish_chunk event. The agent"
" is responsible for interpreting the information present in the 'data' buffer. This is"
" provided for backwards-compatibility support only. Agents should prefer to use relevant"
" JVMTI events and functions above listening for this event. Previous publish_chunk"
" event was inherently unsafe since using the JNIEnv could cause deadlocks in some scenarios."
" The current version does not have these issues.",
{
{ "type", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "data_size", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "data", JVMTI_KIND_IN_BUF, JVMTI_TYPE_JBYTE, false },
});
if (error != OK) {
return error;
}
error = add_extension(
ArtJvmtiEvent::kObsoleteObjectCreated,
"com.android.art.heap.obsolete_object_created",
"Called when an obsolete object is created.\n"
"An object becomes obsolete when, due to some jvmti function call all references to the"
" object are replaced with a reference to a different object. After this call finishes there"
" will be no strong references to the obsolete object anywere. If the object is retrieved"
" using GetObjectsWithTags its type (class) may have changed and any data it contains may"
" have been deleted. This is primarily designed to support memory tracking agents which make"
" use of the ObjectFree and VMObjectAlloc events for tracking. To support this use-case if"
" this event is not being handled it will by default act as though the following code was"
" registered as a handler:\n"
"\n"
" void HandleObsoleteObjectCreated(jvmtiEnv* env, jlong* obsolete_tag, jlong* new_tag) {\n"
" jlong temp = *obsolete_tag;\n"
" *obsolete_tag = *new_tag;\n"
" *new_tag = temp;\n"
" }\n"
"\n"
"Note that this event does not support filtering based on thread. This event has the same"
" restrictions on JNI and JVMTI function calls as the ObjectFree event.\n"
"\n"
"Arguments:\n"
" obsolete_tag: Pointer to the tag the old object (now obsolete) has. Setting the pointer"
" will update the tag value.\n"
" new_tag: Pointer to the tag the new object (replacing the obsolete one) has. Setting the"
" pointer will update the tag value.",
{
{ "obsolete_tag", JVMTI_KIND_IN_PTR, JVMTI_TYPE_JLONG, false },
{ "new_tag", JVMTI_KIND_IN_PTR, JVMTI_TYPE_JLONG, false },
});
if (error != OK) {
return error;
}
art::Runtime* runtime = art::Runtime::Current();
if (runtime->GetJniIdType() == art::JniIdType::kIndices && IsFullJvmtiAvailable()) {
error = add_extension(
ArtJvmtiEvent::kStructuralDexFileLoadHook,
"com.android.art.class.structural_dex_file_load_hook",
"Called during class load, after a 'RetransformClasses' call, or after a 'RedefineClasses'"
" call in order to allow the agent to modify the class. This event is called after any"
" non-can_retransform_classes ClassFileLoadHookEvents and before any"
" can_retransform_classes ClassFileLoadHookEvents. The transformations applied are"
" restricted in the same way that transformations applied via the "
" 'com.android.art.class.structurally_redefine_classes' extension function. The arguments"
" to the event are identical to the ones in the ClassFileLoadHook and have the same"
" semantics.",
{
{ "jni_env", JVMTI_KIND_IN, JVMTI_TYPE_JNIENV, false },
{ "class_being_redefined", JVMTI_KIND_IN, JVMTI_TYPE_JCLASS, true },
{ "loader", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, false },
{ "name", JVMTI_KIND_IN_PTR, JVMTI_TYPE_CCHAR, false },
{ "protection_domain", JVMTI_KIND_IN, JVMTI_TYPE_JOBJECT, true },
{ "dex_data_len", JVMTI_KIND_IN, JVMTI_TYPE_JINT, false },
{ "dex_data", JVMTI_KIND_IN_BUF, JVMTI_TYPE_CCHAR, false },
{ "new_dex_data_len", JVMTI_KIND_OUT, JVMTI_TYPE_JINT, false },
{ "new_dex_data", JVMTI_KIND_ALLOC_BUF, JVMTI_TYPE_CCHAR, true },
});
} else {
LOG(INFO) << "debuggable & jni-type indices are required to implement structural "
<< "class redefinition extensions.";
}
// Copy into output buffer.
*extension_count_ptr = ext_vector.size();
JvmtiUniquePtr<jvmtiExtensionEventInfo[]> out_data =
AllocJvmtiUniquePtr<jvmtiExtensionEventInfo[]>(env, ext_vector.size(), &error);
if (out_data == nullptr) {
return error;
}
memcpy(out_data.get(),
ext_vector.data(),
ext_vector.size() * sizeof(jvmtiExtensionEventInfo));
*extensions = out_data.release();
// Release all the buffer holders, we're OK now.
for (auto& holder : char_buffers) {
holder.release();
}
for (auto& holder : param_buffers) {
holder.release();
}
return OK;
}
jvmtiError ExtensionUtil::SetExtensionEventCallback(jvmtiEnv* env,
jint extension_event_index,
jvmtiExtensionEvent callback,
EventHandler* event_handler) {
if (!IsExtensionEvent(extension_event_index)) {
return ERR(ILLEGAL_ARGUMENT);
}
ArtJvmTiEnv* art_env = ArtJvmTiEnv::AsArtJvmTiEnv(env);
jvmtiEventMode mode = callback == nullptr ? JVMTI_DISABLE : JVMTI_ENABLE;
// Lock the event_info_mutex_ while we set the event to make sure it isn't lost by a concurrent
// change to the normal callbacks.
{
art::WriterMutexLock lk(art::Thread::Current(), art_env->event_info_mutex_);
if (art_env->event_callbacks.get() == nullptr) {
art_env->event_callbacks.reset(new ArtJvmtiEventCallbacks());
}
jvmtiError err = art_env->event_callbacks->Set(extension_event_index, callback);
if (err != OK) {
return err;
}
}
return event_handler->SetEvent(art_env,
/*thread=*/nullptr,
static_cast<ArtJvmtiEvent>(extension_event_index),
mode);
}
} // namespace openjdkjvmti